Function compile_to_plasticine 

pub fn compile_to_plasticine(
    source: &str,
) -> Result<PlasticineArtifact, ParseError>

Compile to the Plasticine target — the open RDU (Prabhakar et al., ISCA 2017), the LOGOS → Plasticine lane. The region unit is the FIRST function, which must be a counted range loop (Spatial Foreach over lo..=hi): it is lowered through the certified crate::codegen_sva::fabric_rtl::LoopFabric, modeled as one metapipeline stage under Spatial’s II definition, placed on the ISCA’17 checkerboard, anchored to the VM at sample inputs, SAT-certified when its body is ALU-only, and emitted as Spatial source. Any other shape gets a NAMED plasticine backend: refusal — an artifact or a typed refusal, never a wrong model.